In my copending U.S. patent application, mentioned supra, there is disclosed an improved cannula provided with a guide bar extending in spaced, parallel relationship to the cannula body. One end of the guide bar is connected with bolts to the cannula. A forward free end of the guide bar, located adjacent and overlying one or more holes formed in the cannula tip through which suction is applied to surgically aspirate fatty tissue, is formed with a guide surface adapted to contact and slide against the patient's skin while the cannula tip is manually directed by the surgeon through the fatty tissue in reciprocating strokes. The guide surface maintains the tip at a constant depth within the tissue so that, upon completion of suction lipectomy, a desired amount of fatty tissue is surgically aspirated while leaving an even thickness layer of tissue intact.
The guide bar is capable of achieving the aforesaid results by allowing the surgeon to move the tip at constant depth through the tissue through a large number of repetative strokes necessary for adequate aspiration without rendering the surgical procedure fatiguing to the surgeon who is now able to grasp the gripping handle of the cannula with both hands.
While my improved cannula, discussed supra, is effective for guiding the cannula tip at constant depth within the tissue, surface portions of the guide bar formed adjacent the guide surface thereof (i.e., between the guide surface and handle) tend to contact the patient's skin together with the guide surface, increasing frictional contact between the skin and guide bar and requiring additional manual force and exertion by the surgeon to reciprocate the cannula. Also, since the guide bar is parallel to the cannula and spaced fairly close thereto, two handed operation is limited to positioning both hands on the gripping portion of the cannula formed at one end thereof opposite the tip. Thus, considerable force is still required to reciprocate the tip through the fatty tissue although the tip is desirably maintained by the guide surface at constant depth. Furthermore, it is often desirable for the surgeon to place his non dominant hand (e.g., left hand if the surgeon is right-handed) on the skin under the guide bar to provide counter pull or counter push against the cannula during reciprocating movement thereof during suction lipectomy. However, the close, parallel spacing of the guide bar tends to prevent the surgeon from contacting the skin, as aforesaid. Also, the close parallel spacing between the guide bar and cannula in my previous invention often renders the surgical procedure difficult when performing surgical lipolysis on areas of the body having sharp contours (e.g., the hips) since surfaces of the guide bar formed adjacent the guide surface tend to contact the skin. A similar problem occurs when attempting to remove deep fatty tissue of the abdominal wall below the Scarpa's fascia.
It is accordingly an object of the present invention to provide an improved cannula that is easily guided by the surgeon at a constant depth so that a desired amount of fatty tissue is surgically aspirated while leaving an even thickness layer of tissue intact.
Another object is to provide an improved cannula that facilitates manuveurability and controllability by permitting two-handed gripping of the cannula by the surgeon during surgical aspiration.
Yet a further object is to provide a cannula that is easy for the surgeon to manipulate, rendering lypolysis less fatiguing for the surgeon to improve safety.
Still another object is to provide an improved cannula that allows the surgeon to place his or her non-dominant hand on the skin under the guide bar for counter pull or counter pushing action against the cannula.
A further object is to provide a cannula that is capable of removing deep fatty tissue from the abdominal wall, such as fatty tissue located below the Scarpa's fascia, and other areas of the body having sharp contours.